Conventionally, a laminated iron core is typically manufactured by processing a strip of electromagnetic steel sheet in coil form (sheet steel strip) by using a progressive die machine. In a progressive die machine, locating holes, slots, and inner teeth are punched out in a steel sheet strip in a sequential manner so as to form various parts of each iron core lamina, and a prescribed number of blanked iron core laminae are bonded to one another to form a laminated iron core. However, when a wire is wound on magnetic pole portions projecting from an inner periphery of a stator core consisting of a laminated iron core, for example, because a space for inserting a winding jig is limited, there is an inconvenience such as that it is difficult to increase the number of the magnetic poles (coils) and/or the number of turns of the wound wire.
To address such a problem, a divided laminated iron core, which is formed by punching, from a sheet steel strip, iron core laminae each having a plurality of core pieces (divided iron core pieces) connected with each other in the circumferential direction and by stacking a plurality of the iron core laminae, has been developed, and, for example, a method for manufacturing a stator core having a ring-shaped yoke and a predetermined number of teeth projecting inward of the yoke by connecting a plurality of divided core pieces, each having a yoke portion and a tooth portion, with each other in an endless manner, and a progressive die machine used in the manufacture of such a stator core are known (see Patent Document 1).